This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. The purpose of this proposal is to test the hypothesis that disturbances in the timing of certain circadian rhythms may contribute to the pathophysiology of premenstrual and seasonal depressions and that correcting these disturbances using chronobiological interventions may result in clinical remission.